As a cost of using a finite supply of fossil fuels continues to rise, increased emphasis is placed on utilizing so-called “alternative” energy sources such as, e.g., solar energy or wind energy. Likewise, increased emphasis is placed on developing more efficient and cost-effective ways of providing basic services such as heating and cooling to residential and commercial buildings.
Radiant heat transfer refers to the transfer of thermal energy by emission of electromagnetic waves from a warmed surface. Electromagnetic waves of the infrared (IR) spectrum travel through a medium such as air, striking objects and people in their path, warming the objects and/or people without directly heating the air itself. A person standing outside in direct sunlight on a winter's day is a good example of the process of radiant heating—the person may feel comfortable without a coat or jacket as long as they remain in the sunlight, but as soon as a cloud obscures the sun the person may quickly seek additional clothing.
In radiant heating systems, thermal energy can be radiated from a heated element such as a wall, floor, or overhead panel to heat people and objects adjacent to the heated elements. Conversely, in radiant cooling systems, cooled elements such as walls, floors, or overhead panels can absorb thermal energy that is radiated from warmer people and objects, making the people adjacent to the cooled elements feel more comfortable. In either case, since most of the thermal exchange occurs directly between the heated or cooled elements and people and objects in a space and not from heating or cooling the surrounding air, occupants can achieve thermal comfort when surrounding air temperatures are significantly higher (radiant cooling) or lower (radiant heating), which can result in significant savings relative to conventional forced air systems that rely primarily upon heating and cooling of the surrounding air.
In radiant systems, the heated or cooled elements can also transfer heat energy to or from objects they are in physical contact with through the mechanism of conduction. Likewise, natural convection currents can be established at an interface between the heating or cooling element and the surrounding air. Thus, even though radiant heat transfer may be the predominate method of transferring heat in a radiant system, conduction and convection may still occur in or be caused by the radiant system.
Radiant heating and cooling systems can be implemented using panels. Conventional cooling and heating panels for placement in ceilings have fixed shapes and pre-placed tubing for water passage. A disadvantage to such a conventional panel is that that, due to their fixed shape and tubing layout, it is not possible to fit the panels to the variety of shapes and obstructions that are frequently encountered in a structure, instead, the structure must accommodate the panel, leaving voids in surface coverage.
Another disadvantage to a conventional panel is that the fixed tubing pattern found in a panel cannot be optimized for different regions in the system, e.g., a residential hallway must be cooled or heated to the same extent as a residential bedroom, which is not the most efficient choice. Another disadvantage to a conventional panel is that each manufacturer purposely designs their panels to work only with their particular accessories, e.g., that manufacturer's particular style of tubing or particular method of attachment.